Electric switch



latented June 12, 1951 UNITED STATES PATENT OFFICE Claims.

The present invention relates to electric switches and more particularly to switches adapted for use with electric lamp sockets of various kinds, such as turn-knob sockets, pull chain sockets, candle sockets, Mogul sockets, and the like.

- It is the general object of the invention to provide a switch structure adapted to be associated with lamp sockets of various types and charact'erized by simplicity and compactness of construction, by a high degree of rigidity and strength and by suitability for manufacture on a large scale at low cost.

More specifically it is an object of the invention to provide an electric switch of the type indicated which is composed entirely of parts which are of simple shape and can be stamped out from fiat insulating stock, whereby complicated molded parts are dispensed with.

It is a further object of the invention to provide an electric switch wherein the supporting structure for the electric terminals and for the operating mechanism is constituted wholly, or

substantially wholly, of two flat plates held in parallel relationship and secured to a fiat third plate by way of a member which at the same time secures the third plate, and hence the switch structure as a whole, to the metallic shell of the lamp socket.

Other features and advantages of the invention In accordance with the present invention, the use of a molded insulating support for the electrically conducting parts of the switch is dispensed with, and a supporting structure is provided which is built up of flat plates which can be stamped to the proper shape and with the necessary apertures from various kinds of flat insulating stock like resins of various kinds, filled or unfilled, resin-impregnated paper stock, etc. Any insulating material capable of being stamped without excessive chipping either at room or at somewhat elevated temperature, will be suitable.

In the form of the invention illustrated in the accompanying drawing, the insulating supporting structure is constituted wholly of the two parallel plates l0 and l l and What may be termed a bottom or third plate l2. The plates l0 and l I may be identical in shape, so that but a single stamping die will be necessary. The plates I 0 and H are held in parallel relationship by the terminal plates I3 and I4, the latter being provided with the usual screws I5 for clamping the will become apparent from the following more detailed description of the invention taken in connection with the accompanying drawing, wherein Fig. 1 is a view in elevation lookin into the interior of a socket structure having my improved switch applied thereto; Fig. 2 is a section taken along the line 2-2 of Fig. 1; Fig. 3 represents a central section taken along the line 33 of Fig. 2; Fig. 4 is a section along the line 4-4 of Fig. 2; Fig. 5 is a view in elevation at right angles to that shown in Fig. 4; while Fig. 6 is a section on a reduced scale showing the twopart separable housing for the metallic screw socket shell and the switch.

It is the usual practice at the present time to manufacture the insulating supporting structure of switches designed for use with lamp sockets, of molded Bakelite or other resin compositions or of porcelain or of other ceramic ware. These moldings are usually of one piece and are rather complicated in structure. This not only necessitates the use of correspondingly complicated molds, but gives rise to considerable loss in the form of a high percentage of rejects as the moldings, whether of resinous or ceramic character, are frequently imperfect.

ends of the lead-in wires to the respective terminal plates. The plates l3 and M are provided with extensions [6, ll, respectively, at each side thereof, the side extensions terminatin in corner projections l8, l9, respectively, which, after having passed through corresponding rectangular slots in the plates Ill, H, are expanded, as can best be seen in Figs. 2 and 5, to secure the terminal plates to the insulating plates [0, II.

By the just-described construction, a quite rigid assembly of the plates [0 and II with the metallic terminal plates is secured. The rigidity is further increased by the provision of shoulders 20, 2|, which fit snugly into corresponding apertures in the plate l2 as shown best in Fig. 2, the shoulders preferably extending for some distance beyond the upper edge of the plate l2, as viewed in said figure, for a, purpose which will be explained hereinafter. The plates I0 and II are further provided with aligned apertures 22, 23 so disposed that a metallic bar 24 passing through the same and snugly fitted therein bears fiat against the lower surface of the plate I2 as viewed in Fig. 2. The bar 24 and the plate [2 are provided with aligned apertures which can be brought into registry with corresponding apertures in the base portion 25 of the metallic inside screw member or shell 26 of a lamp or other socket. The metal plate 24 can then be secured to the socket shell 26 by means of rivets 21 or other fastening device.

The base 25 of the socket shell 26 is provided with the usual opening 28 through which contact is made between the switch structure and the lamp screwed into the socket. The opening 28 is provided with straight parallel sides, as seen in Fig. l, and the projecting shoulders Zil, 2| are so disposed that they fit snugly against such sides of the aperture 23. In this way additional support is provided for the plates Hi and il and at the same time rotation of the shell 26 on the plate 12 is prevented. It may be pointed out that although the plate !2 is shown as circuiar in shape so as to conform to the outline of the shell 26, such shape is not essential.

The terminal plate M is in electrical contact with a metallic conductor strip 29 which is apertured to receive one of the side extensions of the terminal plate M before the corner projections l9 are expanded, such corner projections in their expanded condition serving both to secure the strip 29 against the surface of the insulating plate II, and to establish conducting contact between the strip and terminal plate. The strip 29 at its opposite end passes through an open-ended slot 38 in the bottom plate 12 and its terminal portion is bent so as to overlie the outer face of plate 12. Thereby it is brought into contact with the metallic shell 26 of th socket when the latter is secured to plate it by the rivets or other devices 21. The outer face of the plate 12 may be slightly rabbeted as shown in Fig. to accommodate the strip 29, but this can be dispensed with where a thin strip is employed.

The other terminal plate l3 extends nearly to the inner face of the plate H, as best seen in Figs. 3 and l, and is provided with an inwardly bent, angularly disposed contact portion 3!. The terminal member i3 is relatively rigid, and with the contact portion 3! there is arranged to cooperate a spring contact member 32. The latter is provided with a pair of ears 33 which are slid under the edges of the plates l 9 and I i, as shown in Fig. 5, said plates being rabbeted to provide sufficient clearance for the ears. The spring con tact 32 is roughly of U-shape, and one end 35 thereof is adapted to be passed through an aperture 34 in plate 12 and be received within the opening 23 of the metallic shell 26, as shown in Figs. 3 and 4. The other end 3'5 extends below the contact portion 3| and is biased away from the latter. It is brought into contact withthe portion 3! by means of an insulating operating member 37 which is fitted onto a non-circular portion 38a of the shaft 38 of the turn-knob S8. The operating member 31' is roughly rectangular in shape and acts as a detent, being provided with depressions 9 at opposite ends which are adapted to engage a bend M in the spring contact member 32 when the latter has been forced into contact with the portion 3! of the terminal plate l3. It will be evident that upon operation of the knob 39 in either direction, contact between the parts 36 and 3! will be made and broken in alternation.

The shaft 38 is provided with a collar 52 interiorly of the plates l5 and I i against which the enlarged portion 38a of the shaft bears to limit the movement of the shaft toward the left; while such enlarged portion limits the movement of the shaft toward the right, as viewed in Fig. 2. The enlarged portion of the shaft may take the form of ribs pinched from the body of the shaft.

In Fig. 6 there is shown my improved switch incorporated in the usual socket structure composed of the separable parts Q3 and id which are provided with the usual insulation 85 and 46. To the part 84 there is secured the nipple 41, while the part 43 is provided with an aperture through which the shaft 38 and turn-knob 39 extend. It will be seen that the plate l2, which is of slightly larger external diameter than the socket shell 36 bears against the shoulder 48 of the part 43, and thereby holds the metallic shell 36 and the switch structure against outward movement.

The complete switch structure with the socket shell 26 can be assembled as a unit (without the turn-knob 39), and inserted into the part 13 through its larger end, as follows: after mounting the plates [0 and il upon the ends of the shaft 38 and positioning the terminal plates l3 and I4 between the plates H), I l, and threading the strip 29 upon the side extension of the terminal plate [4, the corner projections 18, iii are expanded. The spring contact member 32 is now placed into position, its end 35 being passed through the aperture 34 as the plate I2 is moved into position to receive the shoulders 20 and 2|. The bar 24 is then passed through the apertures 22 of the plates l9 and l i, after which the socket shell 26 is placed against the outer face of the plate l2 and the said shell, plate l2, and bar 2 riveted together. Care is taken that the end of the strip 29 is in contact with the shell 26 before the riveting takes place. The assembled structure is then inserted through part it, the cooperating part 44 is fitted thereon, and finally the knob 38 is force-fitted or otherwise secured to the shaft 38.

It will be seen from the foregoing that I have provided a switch mechanism in which the supporting insulating structure is composed of simple plates between which the terminal plates and operating member for the switch are disposed, the various parts being capable of assembly as a unit and inserted as such within the housing sections of the socket structure.

It will be evident that while .I have shown my invention as embodied in a switch operated by a turn-knob, it can easily be adapted, as will be evident to those skilled in the art, for use with other devices for operating the spring contact member 32 or equivalent contact or bridging member. Thus, with a pull chain the known ratchet devices for imparting limited movement to a shaft and also a star Wheel or the like for operating the spring contact member, can be employed. Similarly, sliding push-button means for operating the switch can be adapted for use with the switch of the present invention.

I claim:

1. In an electric switch, the combination of a pair of parallel plates of insulating material, a third plate of insulating material disposed at right angles to said parallel plates, the latter having shoulders received within elongated apertures in the third plate, a pair of spaced terminals positioned between the parallel plates at opposite ends thereof and secured thereto, said terminals acting to space the said parallel plates, a metallic lamp socket member bearing against the outer face of said third plate, a bar bearing against the underface of the said third plate and passing through aligned apertures in the parallel plates, means securing the said bar, third plate and socket member to each other, a conducting strip in contact with one of the terminals and having a portion clamped between the socket member and the third plate, whereby electric contact is maintained between the said terminal and the socket member, a conducting spring disposed between the parallel plates and biased away from the other terminal and having a portion passing through the third plate apertures in the parallel plates for locking the parallel plates to the third plate, a pair of terminals disposed between the parallel plates, at opposite ends thereof, said terminals having side portions passing completely through elongated apertures in the parallel plates,-the said side portions having projections which are expanded against the outer surface of the parallel plates to lock the latter to the terminals, a movable contact member located between the parallel Iplates, and means for operating such member.

3. A switch according to claim 2, wherein the shoulders extend beyond the outer face of the third plates and are adapted to bear against the sides of the opening of a lamp socket member secured to the third plate.

4. In an electric switch, an insulating support for the conducting parts of the switch, comprising a pair of parallel plates of insulating material, means for spacing said plates in parallel relation, a third plate of insulating material disposed at right angles to said parallel plates and provided with apertures through which the parallel plates pass, said parallel plates having registering openings therein, a bar passing through said openings and bearing against the third plate, and means for securing the bar to the third plate to thereby lock the parallel plates to such late.

5. A combined lamp socket and switch comprising a pair of identical parallel plates of insulat- 6 v ing material, a third plate of insulating material disposed at right angles to said parallel plates, the latter having shoulders received within elongated apertures in the third plate and protruding beyond the third plate, a pair of spaced terminals positioned between the parallel plates at opposite ends thereof and secured thereto, said terminals acting to space the said parallel plates, a metallic lamp socket member bearing against 1 the outer face of the third plate and having an aperture in its base defined in part by parallel sides which engage the outer surfaces of said shoulders, a bar bearing against the underface of said third plate and passing through aligned apertures in the parallel plates, means to secure the said bar, third plate and socket member to each other, a conducting strip in contact with one of the terminals and having a portion clamped between the socket member and the third plate, a movable contact disposed between the parallel plates adapted to make and break contact with the other terminal and having a portion passing through the third plate and into the aperture in the base of the socket member, and means for operating the movable contact.

JOSEPH FIGUEIRA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 346,020 Brown July 20, 1886 453,455 White June 2, 1891 467,958 Silvey Feb. 2, 1892 662,510 Warner Nov. 27, 1900 692,458 Koltonski Feb. 4, 1902 1,684,268 Hays Sept. 11, 1928 2,128,731 Popp Aug. 30, 1936 2,368,679 Popp Feb. 6, 1945 

